There have conventionally been proposed a variety of medical guidewires for guiding, for example, a catheter which is used by being inserted into tubular organs such as blood vessels, digestive tracts, and ureters, and intracorporeal tissues for treatment or test. The guidewires include those with a structure where a double coil is provided at a distal portion of a core shaft (e.g., see Japanese Translation of PCT Publication Nos. 6-501179 and 2006-511304), those using a stranded wire made up of a plurality of strands inside a coil (e.g., see Japanese Patent Application Laid-Open No. 2008-161491), and those provided with a flat portion at the tip of a core shaft (e.g., see Japanese Patent Application Laid-Open No. 2005-103171).
Generally, the guidewire is required to have flexibility on the front side (distal side) of the guidewire and rotation followability to transmit a rotation performed by an operator from the rear side (proximal side) to the front side of the guidewire.